Coking retort oven



April 16, 1935.

J. VAN ACKEREN COKING RETORT OVEN Filed June 8, 1931 2 Sheets-Sheet 1 INVENTOR. Jase oh 1/0/7 fiche/e0,

T \QQRUMW A ril 16, 1935. .1. VAN AckEREN 1,997,759

COKING RETOR'I' OVEN Filed June 8, 1931 2 Sheets-Sheet 2 f/ElfFPLLV wflrll l/lfblr l .lll.

Patented Apr. 16, 1935 UNITED STATES PATENT OFFICE COKING RETORT OVENJoseph van Ackeren, OHara Township, Allegheny County, Pa., assignor toThe Koppers Company of Delaware, a corporation of Delaware ApplicationJune 8, 1931, Serial No. 542,727

2 Claims.

My invention relatesto coking retort ovens and particularly to ovens ofthe Becker cross-over type in which the flame flues of adjacent heatingWalls are connected in pairs for operation in series.

In the operation of coking retort ovens with relatively high ovenchambers, it is desirable that the flames of combustion in the heatingwalls be elongated in order that the heat of combustion may .bedistributed uniformly throughout the height of the oven chamber. Variousmethods have been proposed for securing this result, including therecirculation of waste gases for mixing with the fuel gas.

It has been proposed, in certain cases, to withdraw gases of combustionor waste gases from certain of the vertical flame flues and to returnthese waste gases through an intermediate flue to the bottoms ofadjacent flues for recirculation. This method is effective in prolongingthe flame of combustion but it possesses the disadvantage that it isapplicable only to flame flues of the hairpin type. The regeneratorarrangement for such flues is undesirable because of counterflowtherebetween.

The methods that have been'proposed heretofore "have also possessed thedisadvantage that the waste gases employed as a diluent have beenintroduced into the flame flue separately and at a point beyond theentrance of the combustible media and the diluent gas is, therefore, notthoroughly mixedwith the combustible media before a flame of relativelyhigh temperature has been produced. Accordingly, there is what may betermed a"hot spot adjacent the bottoms of the flame flues regardless ofthe fact that the flames have been elongated by the diluent gas in theremainder of the flame flue.

.In accordance with the present invention, I provide a construction andmethod of operation whereby waste gases are recirculated and mixed withthe combustible media comprising fuel gas and air before the latter isadmitted to the flame flues. By means of this arrangement, the hot spotsthat have been referred to above are eliminated since all of the gas inthe flame flue has been uniformly diluted. 7

These results have been secured by means of a vertical duct in each ofthe partition walls between the flame flues, the vertical ducts beingconnected to the tops of adjacent flame flues and to conduits below thebottoms of the flame flues. These conduits are provided with arestricted orifice whereby, they have an injector or Venturi effect.

The flow of combustible media through the orifice causes waste gas to bewithdrawn through the vertical duct and to be thoroughly mixed with thecombustible media as all 'of these gases pass through the orificeandinto the corresponding flame flue. r

The details of my invention will be described in connection'withtheaccompanying drawings, in

which Figure 1 is a view, in transverse vertical section, of a coke-ovenbattery embodying my invention, taken partially on line A.--A andpartially on line 3-3 of Fig. 2;

' Fig. 2 is a fragmentary View, in longitudinal vertical section, online IIII of Fig. 1;

Fig. 3 is an enlarged fragmentary View of a portion of the heating wallof Fig. 1; and

Fig. 4 is an enlarged View, in horizontal section, taken on line IVIV1ofFig. 2.

Referring to the drawings, a coke-oven battery I comprises a series of.horizontal coke-oven chambers 2 and heating walls 3 therefor thatalternate therewith. The battery is provided with a roof or top 4,through which extend charging openings 5 for the several oven chambers.Each oven chamber is also provided with a gas offtake opening 6 that isconnected by means of an ascension pipe I to a collecting main 8.

The side walls In of the battery are retained in position by means ofthe usual vertical buckstays l l. Intermediate horizontal brickwork l2extends beneath the ovenchambers 2 and the heating walls 3 and separatesthem from a series of crosswise regenerators l3 that extend throughoutthe width of the battery.

Producer gas may be supplied to the battery from a gas main [4 that isconnected through reversing boxes [5 to the sole flues l6 of theregenerators. The reversing boxes l5 are also connected by means ofvertical ducts I1 to waste gas mains I8 that are in turn connected tothe usual stack (not shown).

Each of the heating walls 3 is provided with a series of vertical flameflues 20 that are connected at their tops through ducts 2| to ahorizontal flue 22. The horizontal flues 22 of adjoining pairs ofheating walls are connected by means of crossover flues 23 whereby theflame'flues of such pairs of adjacent walls are connected in series foralternate operation in opposite directions of flow of gasestherethrough.

Each of the vertical flame flues 20 is connected to two regenerators I3by means of inclined ducts 24 and 25 and a conduit 26 by which means airand producer gas are supplied to the flame flues or waste gases arewithdrawn therefrom according to the direction of flow of gases throughthe heating walls.

Each conduit 26 which opens into the bottom of the corresponding flameflue 20 is provided with a restricted orifice or throat 21 whereby thepassage of air and producer gas therethrough produces a Venturi orinjector effect. Between adjacent flame flues 20 are partition walls 28of the usual bottle bricks.

In the central portion of each of the partition walls 28 is a verticalduct 29 that is connected at its upper end to the tops of the adjoiningflame flues 20 through openings 30. The outer edges of the partitionwalls 28 are not enlarged by reason of the ducts 29 and the normaleffective width of the heating area of each flame flue is notdiminished.

The ducts 29 are connected at their lower ends to the conduits 26 belowthe restricted orifice 21. This arrangement insures that waste gaseswithdrawn from the tops of the flame flues will mix with the air and gasfrom the inclined ducts 24 and 25 and will be injected through theconduits 26 and into the bottoms of the flame flues 20.

In the preferred arrangement, each vertical duct 29 except those at theends of the heating wall is connected to the tops of both adjoiningflame flues and also to both adjacent conduits 26. This arrangementinsures equalization of the recirculating system for waste gases.

The battery is also adapted for operation with coke-oven gas as fuel. Acoke-oven gas main 32 supplies each heating wall 3 through a gas gun 33and a horizontal duct 34 that is connected by means of branch ducts tonozzles 36 in the several flame flues.

In the operation of a coke-oven battery constructed in accordance withmy invention, air and producer gas are supplied through certain of thereversing boxes 45, regenerators l3, inclined ducts 24 and 25 andconduits 26 to the flame flues of one heating wall of each pairconnected in series by means of the crossover flues 28. The preheatedair and producer gas enter the conduits 26 below the restricted oriflce21 and pass upwardly into the flame flues 20 for combustion therein. Thesuction created by the movement of the air and producer gas through theconduits 28 causes waste gases to be withdrawn downwardly through thecorresponding vertical ducts 28 from the tops of the flame flues 20connected thereto, as indicated by arrows in Fig. 3.

The waste gases and combustible media are thoroughly mixed by theirpassage through the threat 2'! and the flames of combustion in the flameflues 20 are, according y. elongated to uniformly distribute the heat ofcombustion throughout the height of the flame flues.

Waste gases pass upwardly from the flame flues 20 through the ducts 2|into the horizontal flue 22 and through the crossover flues 28 into thehorizontal flue 22 of the adjacent wall of each pair for distributioninto the flame flues connected thereto. The waste gases then flowdownwardly through the conduits 26, inclined ducts 2| and and theregenerators connected thereto, reversing boxes l5 and vertical ductsI'l into the waste gas main I 8.

This operation continues for a desired period, whereupon the reversingboxes are adjusted by the usual reversing mechanism to reverse the flowof gases throughout the battery. The outflow regenerators 13 then becomeinflow regenerators for air and producer gas while the inflowregenerators now receive waste gases from the heating Walls in whichcombustion occurred during the previous reversal period. The operationduring this period is identical with that of the preceding period exceptthat the direction of flow of gases through the battery is reversed.

The provision of the restricted orifice or throat for the conduits belowthe bottoms of the flame flues causes an injector effect for positivelywithdrawing gases through the vertical ducts in the partition walls andfor forcing the waste gases thus withdrawn into intimate mixture withthe combustible media before the latter enters the flame flues. Theflames are thereby elongated and there is no production of hot spotsimmediately above the entrance of the combustible gases into the flameflues.

When coke-oven gas is employed, the principal diflerence in operation isthat all of the inflow regenerators conduct air while rich gas issupplied to the nozzles of the corresponding heating walls. Waste gasesare withdrawn through the ducts 28 and are mixed with the air before itenters the flame flues. The flames are thus elongated because of thedilution of the oxygen content of the air.

The provision of the vertical ducts in the partition walls between theflame flues does not diminish the area of contact between the flames ofcombustion in the flame flues and the walls of the oven chambers andthus does not diminish the area of the surface actually heated by theflame flues. This arrangement avoids the areas of relatively lowtemperature that may be caused when the waste gases are returned throughflues between those in which combustion occurs.

My invention is particularly applicable to coke ovens of .the Beckercross-over type with their extremely desirable arrangement of theregenerators in which any counterflow between adJa cent regenerators maybe avoided.

The foregoing and other advantages will be appreciated by those skilledin the art of construction and operation of coke-oven batteries.

I claim as my invention:

1. A coking retort oven structure comprising an oven chamber, twoheating walls therefor having vertical combustion flues adjacent eachother, horizontal flow-duct-means provided with a confiningbottom-structure having ports in substantial alignment with the verticalflues and above the tops of the combustion flues and crossover ductscrossing over said chamber and communi cably connecting the horizontalflow-duct-means in the two heating wallswith each other to connect thecombustion flues of the two walls in series for concurrent operationalternately in opposite directions, partition walls between andseparating adjacent vertical combustion flues, said partitions and thevertical flues therebetween terminating at their tops at a spaceddistance below the bottom of said horizontal flow-ductmeans so as toprovide a horizontal gas flow channel communicating in common with thetops of a plurality of the flues and located between the latter and thebottoms of the horizontal flowduct-means, and a vertical duct in each ofsaid partition walls and communicating with each of the adjacentcombustion flues through a combustion medium Venturi inlet thereforbelow the bottoms of the combustion flues and with the horizontal gasflow channel at the top of the flues, whereby to eifect, duringoperation of the vertical combustion flues for combustion, recirculationin an upward direction through the combustion flues or waste gas toelongate the flame of combustion in the combustion fiues.

2. A coking retort oven structure comprising an oven chamber, twoheating walls therefor having vertical combustion flues adjacent eachother, horizontal flow-duct-means provided with a confiningbottom-structure having ports in substantial alignment with the verticalfines and above the tops of the combustion flues and crossover ductscrossing over said chamber and communicably connecting the horizontalflow-duct-means in the two heating walls with each other to connect thecombustion flues of the two walls in series for concurrent operationalternately in opposite directions, partition walls between andseparating adjacent vertical combustion flues, said partitions and thevertical flues therebetween terminating at their tops at a spaceddistance below the bottom of said horizontal fiow-duct-means so as toprovide a horizontal gas flow channel communicating in common with thetops of a plurality of the fiues and located between the latter and thebottoms of the horizontal flow-ductmeans, and a vertical duct in each ofsaid partition walls and communicating with one of the adjacentcombustion flues through a combustion medium Venturi inlet thereforbelow the bottom of the combustion flue and with the horizontal gas flowchannel at the top of the flues, whereby to effect, during operation ofthe vertical combustion fiues for combustion, recirculation in an upwarddirection through the combustion fines of waste gas to elongate theflame of combustion in the combustion flues.

JOSEPH VAN ACKEREN.

